Mouth ulcers are painful lesions or sores that develop inside the oral cavity. They affect areas including the gums, tongue, inner cheeks, lips, or even the roof of the mouth. They can vary in size and appearance but are often white, yellow, or gray with inflamed edges. They happen in people as well as dogs, and to a lesser extent, felines.
Mouth ulcers in people can be caused by a variety of factors, including:
- Minor injuries: Biting the inside of the cheek, brushing too hard, or eating excessively hot food.
- Stress and hormonal changes: Emotional stress or hormonal fluctuations can trigger ulcers.
- Infections: Viral causes (most notably the herpes virus), bacterial, or fungal infections can be an underlying cause.
- Underlying health conditions: Autoimmune diseases, inflammatory bowel disease, diabetes, and celiac disease can be linked to mouth ulcers.
Common Causes of Mouth Ulcers in Dogs
Mouth ulcers in dogs stem from a variety of underlying conditions. Some common causes include:
- Inflammation due to dental disease. ‘Kissing lesions’ is a common term used when associated with dental disease. They occur when plaque and calculus on the surface of the teeth cause focal ulceration on the oral mucosa where the inner cheek rests on the tooth surface
- Canine Chronic Ulcerative Stomatitis—This is a hypervigilant immune response that causes widespread oral ulceration.
- Immune-mediated diseases like eosinophilic granulomas and pemphigus
- Metabolic disorders, such as advanced kidney disease. Uremic ulcers can occur with advanced kidney disease.
- Trauma from burns, mechanical injuries, or exposure to chemicals. This is mostly seen in puppies and young dogs who enjoy active exploration with their mouth.
- Idiopathic cases, where no specific cause is identified
Signs to Watch For
Mouth ulcers in dogs can be quite painful and may affect their ability to eat, drink, or even play comfortably. Some common signs to watch for include:
- Excessive drooling or difficulty swallowing
- Pawing at the mouth or rubbing their face on surfaces
- Reluctance to eat or sudden loss of appetite
- Bad breath (secondary to infection or inflammation). Oral malodor is often the first sign that an imbalance is present in the oral cavity.
- Visible sores or lesions inside the mouth, gums, or tongue
- Bleeding or inflamed areas in the oral cavity
- Whimpering or signs of pain when chewing or opening the mouth
- Lethargy. Reclusive behavior is not uncommon when pain is present.
- Change in behavior. Some dogs may appear cranky or snap due or oral pain. Chronic pain affects behavior.
Treatment Options for Mouth Ulcers in Dogs
Treatment options can vary. There are several effective treatment options for dog mouth ulcers, depending on the underlying cause. Some common approaches include:
- Veterinary-prescribed medications such as antibiotics or anti-inflammatory drugs
- Specialized dental rinses to reduce bacteria and promote healing
- Dietary modifications to avoid systemic food allergies that may have oral ulcers as a component. This is also important for kidney disease and uremic ulcers. A concurrent consultation with a veterinary dermatologist and veterinary internist may be beneficial as a team-oriented approach to management.
- Pain management—This is of utmost importance. The mouth is the first part of the GI tract, and a painful mouth makes it very challenging for a patient to be able to eat and obtain the necessary nutrients for optimal health.
- Environmental changes to remove exposure to potential irritants. This can include plants, sharp objects, as well as cleaning agents, and other chemicals and solvents.
- Preventive care/Environmental mitigation in young dogs and puppies to reduce recurrence. Electrical outlets and cords should be covered to prevent inadvertent chewing.
Dog Oral Care in Bozeman, Montana
If you have concerns about your dog’s oral health and comfort, please reach out to us at Montana Pet Dentistry and Oral Surgery to schedule a consultation appointment.
Images used under creative commons license – commercial use (06/13/2025) Photo by Anna Dudkova on Unsplash